JayMan...thanks for the info. New to this and cant get to my pond but maybe 20-30 days of the year. early stages of trying to get it to a suitable fishery. No doubt there is a lot of mucky stuff on the bottom since its surrounded by trees. It is a sand bottom and supposedly the pine trees stain the water a darkish tone. Cant see through the water more than a couple of feet. Wonder some times if the mighty oak leaf isnt more of a problem than the birches and maples. I know on land my oak leaves break down very slowly. I removed the small oaks that were right at the pond edge and am about to start removing some of the 200 or so birch...soon as I figure what to do with the remains.